Local news affiliate KCTV reports that Lammers' mother contacted police on Thursday, saying that her son had purchased assault rifles similar to those used in the Aurora, Colorado movie theater shooting and that she was concerned that he might try to shoot people at the opening of The Twilight Saga: Breaking Dawn - Part 2.

Lammers reportedly bought more than 400 rounds of ammunition in addition to the rifles.

According to court documents obtained by KCTV, Lammers confirmed his mother's fears in talking with authorities. The papers go on to claim that Lammers expressed plans to also target a Walmart, which would have more ammunition in the event that he ran out.

According to KCTV, Lammers was charged Friday with first-degree assault, making a terroristic threat and armed criminal action. He is reportedly being held on a $500,000 bond.